A rock breaking roller cutter with built-in flexible element and a cutter monitoring method

Abstract

The present application discloses a rock breaking roller cutter with a built-in flexible element and a tool monitoring method, which relates to the technical field of rock breaking roller cutters, and comprises a cutter shaft, a cutter ring and a sensor assembly; the cutter shaft has a stepped hole running through the axial direction; the cutter ring is rotatably connected to the cutter shaft through a bearing assembly, and is used for rock breaking and excavation; the sensor assembly comprises a flexible element and a vibration monitoring sensor; both ends of the flexible element are fixedly connected to the step surface of the stepped hole through a pre-tightening assembly, so that the flexible element is installed in the stepped hole; the vibration monitoring sensor is connected to the outside of the flexible element, so that the flexible element can amplify the vibration signal of the cutter shaft, thereby realizing real-time monitoring of the working status of the tool by the vibration monitoring sensor.

Description

Technical Field

[0001] The present application belongs to the technical field of rock breaking cutters, and specifically relates to a rock breaking cutter with a built-in flexible element and a cutter monitoring method. Background Art

[0002] The shield machine cutterhead is a critical component in tunneling operations, and its performance directly impacts tunneling speed and efficiency. The disc cutters on the cutterhead, as a crucial component of the tool, are responsible for rock breaking and tunneling. Because the disc cutters are subject to high forces, rapid wear, and complex environments during operation, real-time monitoring of the cutter's operating status is essential for timely and effective control.

[0003] Existing tool monitoring systems often use external sensors, attaching multiple sensors to the outside of the tool. These sensors are typically attached to the cutter ring, toolholder, or bearing. Tool condition monitoring relies on multiple sensors to measure different physical quantities, such as vibration, temperature, and cutting force. Installing multiple sensors not only requires a large amount of space, but also often results in interference between the signals from different sensors, leading to inaccurate data acquisition and significantly increasing the complexity. Furthermore, if the sensors are installed on the toolholder, the distance from the cutter ring means the acquired data may not truly reflect the tool's operating condition, resulting in poor accuracy. Furthermore, these non-integrated, packaged sensors are susceptible to environmental factors, making long-term, continuous monitoring impossible and subject to the risk of signal instability. Furthermore, tools face harsh conditions during the cutting process, such as high temperature, high humidity, dust, and strong vibration. Sensor data collection is susceptible to external interference, resulting in poor stability for external sensors and even damage to the equipment. Furthermore, these non-integrated, packaged sensors often require numerous cables to connect them, making assembly and layout difficult given the limited space within the tool. Summary of the Invention

[0004] The present application provides a rock-breaking roller cutter and tool monitoring method with a built-in flexible element to solve the above-mentioned technical problems that multiple sensors not only require a large space, but also the signals often interfere with each other, resulting in inaccurate data acquisition or greatly increased complexity; due to the influence of environmental factors, long-term and continuous monitoring cannot be achieved; the tool will face harsh conditions such as high temperature, high humidity, dust, strong vibration, etc. during the cutting process, and the data acquisition of the sensor is easily affected by external interference; a large number of cables are required to connect, which leads to difficulties in assembly and layout when the internal space of the tool is limited.

[0005] The technical solutions adopted in this application are:

[0006] A rock breaking disc cutter with a built-in flexible element, comprising a cutter shaft, a cutter ring and a sensor assembly;

[0007] The knife shaft has a stepped hole extending through the axial direction;

[0008] The cutter ring is rotatably connected to the cutter shaft through a bearing assembly and is used for rock breaking and tunneling;

[0009] The sensor assembly includes a flexible element and a vibration monitoring sensor; both ends of the flexible element are fixedly connected to the step surface of the stepped hole through a pre-tightening assembly, so that the flexible element is installed in the stepped hole; the vibration monitoring sensor is connected to the outside of the flexible element so that the flexible element can amplify the vibration signal of the tool shaft, thereby realizing real-time monitoring of the tool working status by the vibration monitoring sensor.

[0010] The rock breaking disc cutter with a built-in flexible element of the present application also has the following additional technical features:

[0011] The flexible element includes a packaging shell, a flexible member and a clamping head;

[0012] A flexible part is connected inside the packaging shell, and both ends of the flexible part are respectively connected to clamping heads connected to the pre-tightening component; the vibration monitoring sensor is connected to the middle position of the outer side of the packaging shell.

[0013] The clamping head is of a cone structure, with the small diameter end of the clamping head facing the flexible member and the large diameter end of the clamping head facing the preload assembly;

[0014] The outer periphery of the small diameter end of the clamping head is provided with an external thread, and the interior of the small diameter end of the clamping head is provided with a connecting groove; the interior of the large diameter end of the clamping head is provided with a positioning hole, and the positioning hole has an internal thread for connecting the pre-tightening component.

[0015] The flexible member includes a flexible member body and flexible connecting members connected to both ends of the flexible member body;

[0016] The flexible part body is connected to the packaging shell, the flexible connecting part extends out of the packaging shell and can partially extend into the connecting groove of the clamping head. The flexible connecting part is provided with a connecting hole, and a positioning pin is passed through the connecting hole and the connecting groove to fasten the flexible part to the clamping head.

[0017] The flexible element further comprises a clamping nut which is threadedly connected to the outer side of the small diameter end of the clamping head and is fitted into the stepped hole through the clamping nut so that the clamping head is positioned in the stepped hole.

[0018] The pre-tightening assembly includes a fixing bolt, a pre-tightening nut and a fastening nut;

[0019] One end of the fixing bolt extends into the positioning hole and is threadedly connected to the clamping head, and the other end of the fixing bolt extends toward the outside of the stepped hole and is connected to the pre-tightening nut. The fastening nut is arranged outside the pre-tightening nut and is fastened to the fixing bolt.

[0020] The end of the fixing bolt extending toward the outside of the stepped hole is provided with a slot; when the pre-tightening nut is screwed onto the fixing bolt, the slot is pressed against the flexible member abutted by the fixing bolt to prevent twisting.

[0021] The inner wall of the stepped hole of the knife shaft is provided with an anodized insulating layer;

[0022] A threaded plug is connected to one end of the stepped hole of the cutter shaft, and an O-ring is connected between the threaded plug and the inner wall of the stepped hole; the threaded plug is also provided with a wiring hole that is connected to the stepped hole, so that a cable can be connected to the vibration monitoring sensor in the stepped hole through the wiring hole;

[0023] The other end of the stepped hole of the cutter shaft is connected to a bolt ear, and the stepped hole is sealed by a threaded plug and the bolt ear. The gap between the sensor assembly and the inner wall of the stepped hole is filled with silicone damping material, so that the sensor assembly is encapsulated in the stepped hole.

[0024] The present application also relates to a tool monitoring method for a rock breaking cutter with a built-in flexible element. Based on the rock breaking cutter with a built-in flexible element described above, the specific steps include:

[0025] The flexible element is excited by the vibration of the cutter ring caused by the cutting force and produces periodic deformation;

[0026] The vibration monitoring sensor detects the vibration frequency of the flexible element and removes the noise through the microprocessor to extract the vibration frequency signal of the knife ring excitation;

[0027] The vibration frequency signal is uploaded to the host computer through the communication unit;

[0028] The host computer inputs the extracted vibration signal and the corresponding cutter working condition classification label into the neural network model to automatically extract features and establish a nonlinear functional relationship between the vibration of the flexible element and the cutting tool's excavation state.

[0029] Based on the nonlinear function relationship and the training of the neural network model, the association between variables is automatically learned and extracted to judge and predict the tool status.

[0030] The method of automatically learning and extracting the association between variables based on the nonlinear functional relationship and the training of the neural network model to predict the tool state specifically includes:

[0031] The sensor component detects the tool's working condition data in real time. Each working condition data corresponds to the time series and frequency domain characteristics of the tool in a specific working state.

[0032] The time series and frequency domain features are preprocessed by the same frequency sampling, clipping and tensor transformation and then input into the neural network model for model training. The neural network model outputs integer numbers, which correspond to various working condition information of the tool to obtain the prediction and fault diagnosis results of the tool.

[0033] Due to the adoption of the above technical solution, the beneficial effects achieved by this application are as follows:

[0034] 1. The present application relates to a rock breaking roller cutter with a built-in flexible element, comprising a cutter shaft, a cutter ring and a sensor assembly; the cutter shaft has a stepped hole running through the axial direction; the cutter ring is rotatably connected to the cutter shaft through a bearing assembly, and is used for breaking rocks and cutting; the sensor assembly comprises a flexible element and a vibration monitoring sensor; both ends of the flexible element are fixedly connected to the step surfaces of the stepped hole through a pre-tightening assembly, so that the flexible element is installed in the stepped hole; the vibration monitoring sensor is connected to the outside of the flexible element so that the flexible element can amplify the vibration signal of the cutter shaft, thereby realizing real-time monitoring of the working status of the tool by the vibration monitoring sensor.

[0035] By connecting the vibration monitoring sensor to the flexible element, and the flexible element is connected to the inside of the tool shaft, the flexible element can deform along with the vibration of the tool shaft, and the vibration signal of the tool shaft can be amplified by the flexible element. Even in a complex working environment, the monitoring signal is still clear, so that the vibration monitoring sensor can more keenly perceive the vibration state of the tool shaft by detecting the flexible element, obtain more accurate information in real time, further improve the sensitivity of tool shaft detection, facilitate long-term and continuous detection, avoid the risk of signal instability, avoid environmental interference, and provide timely feedback on the true working state of the tool, thereby improving the accuracy and timeliness of detection.

[0036] 2. As a preferred embodiment of the present application, the clamping head has a conical structure, the small diameter end of the clamping head faces the flexible part, and the large diameter end of the clamping head faces the preload assembly; the small diameter end of the clamping head is provided with an external thread on the outer periphery, and the small diameter end of the clamping head is provided with a connecting groove inside; the large diameter end of the clamping head is provided with a positioning hole inside, and the positioning hole has an internal thread for connecting the preload assembly.

[0037] The variable diameter structure of the clamping head makes it easier to insert the small diameter end of the clamping head into the stepped hole. The variable diameter structure allows the clamping head to be more securely installed in the stepped hole, which facilitates the opening of an external thread at the small diameter end of the conical structure of the clamping head, so that the clamping nut is threadedly connected to the outside of the clamping head, further increasing the secure connection between the clamping head and the stepped hole. Even if the tool vibrates strongly, it will not affect the movement of the position of the flexible element, thereby enhancing the accuracy and sensitivity of detection.

[0038] 3. As a preferred embodiment of the present application, the pre-tightening assembly includes a fixing bolt, a pre-tightening nut and a fastening nut; one end of the fixing bolt extends into the positioning hole and is threadedly connected to the clamping head, and the other end of the fixing bolt extends toward the outside of the stepped hole and is connected to the pre-tightening nut, and the fastening nut is arranged on the outside of the pre-tightening nut and is fastened to the fixing bolt.

[0039] A fastening nut is provided on the outside of the pre-tightening nut at both ends of the flexible element and is connected to a fixing bolt. The pre-tightening nut realizes the pre-tightening of the flexible element. The corresponding pre-tightening force can determine an initial natural frequency. The fastening nut realizes the final tightening of the flexible element, ensuring that the flexible element, the pre-tightening assembly and the flexible element are stable in the knife shaft.

[0040] 4. As a preferred embodiment of the present application, a slot is provided at the end of the fixing bolt extending toward the outside of the stepped hole; when the pre-tightening nut is screwed onto the fixing bolt, the slot is pressed against the flexible member to which the fixing bolt is abutted to prevent twisting.

[0041] The tool is abutted into the slot so that the fixing bolt does not rotate with the pre-tightening nut. This arrangement prevents the flexible element from twisting with the rotation of the pre-tightening nut, causing torsional deformation and affecting the detection of the vibration monitoring sensor.

[0042] As a preferred embodiment of the present application, a threaded plug is connected to one end of the stepped hole of the cutter shaft, and a bolt lug is connected to the other end of the stepped hole of the cutter shaft. The preload assembly, clamping head, and flexible element are encapsulated within the cutter shaft, isolating it from environmental contamination, protecting the operational stability of the vibration monitoring sensor, and ensuring the safety of the entire cutter shaft during transportation and installation. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0044] Figure 1 This is a schematic structural diagram of a rock breaking cutter with a built-in flexible element according to one embodiment of the present application;

[0045] Figure 2 This is a schematic diagram of the internal structure of a cutter shaft of a rock breaking disc cutter with a built-in flexible element according to one embodiment of the present application;

[0046] In the figure,

[0047] 1. Cutter shaft; 2. Wiring hole; 3. Fixing bolt; 4. Clamping head; 5. Flexible part; 6. Pre-tightening nut; 7. Fastening nut; 8. Slot; 9. Bolt lug; 10. Package shell; 11. Vibration monitoring sensor; 12. Clamping nut; 13. Locating pin; 14. Threaded plug; 15. Bearing assembly; 16. Cutter ring. DETAILED DESCRIPTION

[0048] In order to more clearly illustrate the overall concept of the present application, a detailed description is given below in an illustrative manner in conjunction with the accompanying drawings.

[0049] In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application may also be implemented in other ways different from those described herein. Therefore, the scope of protection of the present application is not limited to the specific embodiments disclosed below.

[0050] In addition, in the description of the present application, it should be understood that the terms "top", "bottom", "inside", "outside", "axial", "radial", "circumferential", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention.

[0051] In this application, unless otherwise expressly specified or limited, terms such as "installed," "connected," "connect," and "fixed" should be understood in a broad sense. For example, they may refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or communication; direct connection or indirect connection through an intermediate medium; and internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0052] In this application, unless otherwise expressly specified and limited, a first feature "above" or "below" a second feature may be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. In the description of this specification, the reference terms "implementation method", "embodiment", "one embodiment", "example" or "specific example" and the like mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in an appropriate manner in any one or more embodiments or examples.

[0053] Example 1

[0054] The present application relates to a rock breaking disc cutter with a built-in flexible element, such as Figure 1-2 As shown, it includes a cutter shaft 1, a cutter ring 16 and a sensor assembly;

[0055] The cutter shaft 1 has a stepped hole extending through the axial direction;

[0056] The cutter ring 16 is rotatably connected to the cutter shaft 1 through the bearing assembly 15 and is used for rock breaking and tunneling;

[0057] The sensor assembly includes a flexible element and a vibration monitoring sensor 11; the two ends of the flexible element are fixedly connected to the step surface of the stepped hole through a pre-tightening assembly, so that the flexible element is installed in the stepped hole; the vibration monitoring sensor 11 is connected to the outside of the flexible element so that the flexible element can amplify the vibration signal of the tool shaft 1, thereby realizing real-time monitoring of the tool working status by the vibration monitoring sensor 11.

[0058] A stepped hole is opened inside the cutter shaft 1, so that the flexible element connected to the vibration monitoring sensor 11 can be installed in the stepped hole. The flexible element and the vibration monitoring sensor 11 can be hidden inside the cutter shaft 1, which simplifies the sensor layout of the equipment, avoids signal interference between multiple sensors in traditional methods, improves the accuracy of data acquisition and simplifies the assembly process. Due to the integrated structural design of the cutter shaft 1 and the flexible element, the maintenance and replacement process of the equipment is simplified, a more convenient operation method is provided, the complexity of equipment maintenance is reduced, and the reliability and durability of the system are enhanced; the vibration monitoring sensor 11 and the flexible element are avoided from being exposed to harsh environments, and damage to the equipment is avoided. The vibration monitoring sensor 11 and the flexible element can be placed close to the cutter ring 16 to clearly detect the working status of the tool throughout the process, and the interference of the harsh environment on the signal of the vibration monitoring sensor 11 can be effectively avoided. Compared with traditional non-integrated sensor tools, it not only saves space but also avoids interference from the external environment to achieve real-time and accurate detection of the tool status.

[0059] By connecting the vibration monitoring sensor 11 to the flexible element, and the flexible element is connected to the inside of the knife shaft 1, the flexible element can deform along with the vibration of the knife shaft 1, and the vibration signal of the knife shaft 1 can be amplified by the flexible element. Even in a complex working environment, the monitoring signal is still clear, so that the vibration monitoring sensor 11 can more keenly perceive the vibration state of the knife shaft 1 by detecting the flexible element, obtain more accurate information in real time, further improve the sensitivity of detection of the knife shaft 1, facilitate long-term and continuous detection, avoid the risk of signal instability, avoid environmental interference, and timely feedback the real working state of the tool, thereby improving the accuracy and timeliness of detection.

[0060] The cutter shaft 1 is provided with a stepped hole penetrating the cutter shaft 1 along the axial direction. The stepped holes are symmetrically distributed on both sides with the central section along the axial direction of the cutter shaft 1 as the center. Figure 1 As shown, the stepped hole includes a first large hole, a first middle hole, a first small hole, a second small hole, a second middle hole and a second large hole connected from left to right, wherein the first large hole and the second large hole are symmetrical, the first middle hole and the second middle hole are symmetrical, the first small hole and the second small hole are symmetrical, the aperture size of the first large hole is larger than the aperture size of the first middle hole, and the aperture size of the first middle hole is larger than the aperture size of the first small hole; the first small hole and the second small hole serve as the main mounting holes of the flexible element, and the aperture sizes of the first small hole and the second small hole need to be adapted to the outer diameter of the flexible element to which the vibration monitoring sensor 11 is connected; the first large hole is used to install the threaded plug 14, the second hole is used to install the bolt ear 9, and the first middle hole and the second middle hole are used to provide space for installing the fixing bolt 3, the pre-tightening nut 6 and the fastening nut 7.

[0061] As a preferred embodiment, the flexible element includes a packaging shell 10, a flexible part 5 and a clamping head 4; the flexible part 5 is connected inside the packaging shell 10, and the two ends of the flexible part 5 are respectively connected to the clamping heads 4 connected to the pre-tightening assembly; the vibration monitoring sensor 11 is connected to the middle position of the outer side of the packaging shell 10.

[0062] The outer side of the flexible element is connected to a packaging shell 10, which encapsulates the internal flexible part 5 in the shell to protect the flexible part 5 from external damage, wear or breakage, and improve the service life of the flexible part 5. The two ends of the flexible part 5 can extend out of the packaging shell 10 respectively, and the purpose is to be used to connect with the clamping head 4, and the flexible part 5 is fixed in the stepped hole through the clamping head 4. Specifically, Figure 1 The orientation shown, Figure 1 The connection between the pre-tightening assembly and the clamping head 4 on the left side is described as an example, and the flexible part 5 is installed in the first small hole and the second small hole of the stepped hole. The end of the flexible part 5 extending from the left end of the packaging shell 10 can be extended into the interior of the clamping head 4 and connected to the clamping head 4 through the positioning pin 13. Since there are pre-tightening assemblies on both sides of the flexible element, the fixing bolt 3 of the pre-tightening assembly described below can be threadedly connected to the clamping head 4, and the flexible element is fixed to the stepped hole of the tool shaft 1 through the pre-tightening assembly.

[0063] As a preferred embodiment, the clamping head 4 has a conical structure, the small diameter end of the clamping head 4 faces the flexible part 5, and the large diameter end of the clamping head 4 faces the preload assembly; an external thread is provided on the outer periphery of the small diameter end of the clamping head 4, and a connecting groove is provided inside the small diameter end of the clamping head 4; a positioning hole is provided inside the large diameter end of the clamping head 4, and the positioning hole has an internal thread for connecting the preload assembly.

[0064] The purpose of the conical structure of the clamping head 4 is that, on the one hand, the variable diameter structure of the clamping head 4 makes it easier to insert the small diameter end of the clamping head 4 into the stepped hole, and the variable diameter structure makes the clamping head 4 more firmly installed in the stepped hole, and the clamping head 4 can be suitable for stepped holes with a wider aperture range. On the other hand, it is beneficial to open an external thread at the small diameter end of the conical structure of the clamping head 4, and add the clamping nut 12 described below to connect it, so that the clamping nut 12 is threadedly connected to the outside of the clamping head 4, and the clamping nut 12 is arranged between the clamping head 4 and the stepped hole, further increasing the fastening connection between the clamping head 4 and the stepped hole. Even if the tool vibrates strongly, it will not affect the movement of the position of the flexible element, thereby enhancing the accuracy and sensitivity of the detection.

[0065] As a preferred embodiment, the flexible member 5 includes a flexible member 5 main body and flexible connecting members connected to both ends of the flexible member 5 main body; the flexible member 5 main body is connected to the packaging shell 10, the flexible connecting member extends out of the packaging shell 10 and can partially extend into the connecting groove of the clamping head 4, and the flexible connecting member is provided with a connecting hole, and a positioning pin 13 is passed through the connecting hole and the connecting groove to fasten the flexible member 5 to the clamping head 4.

[0066] The flexible part 5 main body of the flexible part 5 can adopt a variety of shapes, such as a cylindrical or square sheet structure. The material of the flexible part 5 main body can be selected from a variety of options, such as metal, rubber, plastic, nylon, etc., and can be selected according to the specific work needs. Flexible connectors are connected to the two ends of the flexible part 5 main body along the length direction. The ends of the flexible connector protruding from the flexible part 5 main body form an integrated structure with the flexible part 5 main body. The flexible connector is preferably made of metal to facilitate the fastening connection of the clamping head 4. The width dimension of the flexible connector is smaller than the width dimension of the flexible part 5 main body. The width dimension of the flexible connector is compatible with the width dimension of the connection groove of the clamping head 4, which facilitates the flexible connector to be inserted into the connection groove for assembly with the clamping head 4.

[0067] like Figure 1 As shown, a connecting hole is provided at one end of the flexible connector near the clamping head 4, and when the flexible connector is extended into the connecting groove, the connecting hole is arranged in the connecting groove, and the opening of the connecting hole corresponds to the opening of the connecting groove, so that the positioning pin 13 can pass through one end of the connecting hole and pass out from the other end of the connecting hole, and then the two ends of the positioning pin 13 are bent so that the flexible connector is limited in the connecting groove, thereby realizing the clamping connection between the flexible element and the clamping head 4.

[0068] As a preferred embodiment, the flexible element also includes a clamping nut 12; the clamping nut 12 is threadedly connected to the outer side of the small diameter end of the clamping head 4, and is fitted into the stepped hole through the clamping nut 12, so that the clamping head 4 is positioned in the stepped hole.

[0069] When in use, the outer thread of the small diameter end of the clamping head 4 is pre-connected with a clamping nut 12. After the flexible connectors on both sides of the flexible element are fastened to the clamping head 4 through the positioning pins 13, the clamping head 4 and the flexible element are installed in the stepped hole, and then the clamping nut 12 is further screwed on the clamping head 4 in the stepped hole until the clamping nut 12 is fastened to the inner wall of the stepped hole, thereby fastening the flexible element and the clamping head 4 to the stepped hole.

[0070] As a preferred embodiment, the pre-tightening assembly includes a fixing bolt 3, a pre-tightening nut 6 and a fastening nut 7; one end of the fixing bolt 3 extends into the positioning hole and is threadedly connected to the clamping head 4, and the other end of the fixing bolt 3 extends toward the outside of the stepped hole and is connected to the pre-tightening nut 6, and the fastening nut 7 is arranged on the outside of the pre-tightening nut 6 and is fastened to the fixing bolt 3.

[0071] After the clamping head 4 and the flexible element are installed in the stepped hole, one end of the fixing bolt 3 of the pre-tightening assembly is threaded into the positioning hole of the clamping head 4 to achieve the positioning installation of the fixing bolt 3 and the clamping head 4. Figure 1 The other end of the fixing bolt 3 on the left side is located in the first middle hole and is threadedly connected to the fixing bolt 3 through the pre-tightening nut 6, so that the fixing bolt 3 is abutted against the step surface formed by the first middle hole and the first small hole, thereby positioning the flexible element and one end of the clamping head 4 in the stepped hole, limiting the left side of the clamping head 4; similarly, Figure 1 One end of the center-right fixing bolt 3 is threaded into the positioning hole of the right clamping head 4. A pre-tightening nut 6 is threaded onto the fixing bolt 3, causing the fixing bolt 3 to abut against the stepped surface formed by the second center hole and the first small hole, thereby positioning the other end of the flexible element and the clamping head 4 within the stepped hole. The pre-tightening nut 6 applies a preload to the fixing bolt 3, which can be adjusted to an appropriate value, further ensuring that the initial natural frequency of the flexible element is within a suitable range.

[0072] In order to further enhance the fastening connection between the clamping head 4 and the flexible element in the stepped hole, a fastening nut 7 is provided on the outside of the pre-tightening nut 6 at both ends of the flexible element and connected to the fixing bolt 3. The pre-tightening nut 6 realizes the pre-tightening of the flexible element. The corresponding pre-tightening force can determine an initial natural frequency on the basis of which the fastening nut 7 realizes the final fastening of the flexible element, ensuring that the flexible element, the pre-tightening assembly and the flexible element are firm in the knife shaft 1.

[0073] As a preferred embodiment, a slot 8 is provided at the end of the fixing bolt 3 extending toward the outside of the stepped hole; when the pre-tightening nut 6 is screwed onto the fixing bolt 3, the slot 8 is pressed against the flexible member 5 to which the fixing bolt 3 is abutted to prevent twisting.

[0074] In order to prevent the flexible element from twisting along with the fixing bolt 3 due to the rotation of the fixing bolt 3 when the pre-tightening nut 6 and the tightening nut 7 are installed, a slot 8 is provided at the end of the fixing bolt 3 extending outward from the stepped hole. When the pre-tightening nut 6 is threadedly connected to the fixing bolt 3, a tool is used to abut against the slot 8, so that the fixing bolt 3 does not rotate along with the pre-tightening nut 6. Thus, the flexible element will not twist along with the rotation of the pre-tightening nut 6, thereby preventing torsional deformation from affecting the detection of the vibration monitoring sensor 11.

[0075] As a preferred embodiment, the inner wall of the stepped hole of the cutter shaft is provided with an anodized insulating layer; one end of the stepped hole of the cutter shaft 1 is connected to a threaded plug 14, and an O-ring is connected between the threaded plug 14 and the inner wall of the stepped hole; the other end of the stepped hole of the cutter shaft 1 is connected to a bolt lug 9, and the stepped hole is sealed by the bolt 3 and the bolt lug 9, and the gap between the sensor assembly and the inner wall of the stepped hole is filled with silicone damping material, so that the sensor assembly is encapsulated in the stepped hole; the threaded plug 14 is also provided with a wiring hole 2 that is connected to the stepped hole, so as to connect the cable to the vibration monitoring sensor 11 in the stepped hole through the wiring hole 2.

[0076] After the preload components at both ends of the flexible element are installed, Figure 1 A threaded plug 14 is installed in the first large hole on the left side, and a bolt ear 9 is installed in the second large hole on the right side, so that the preload assembly, the clamping head 4 and the flexible element are encapsulated inside the cutter shaft 1, isolating the environmental pollution, protecting the working stability of the vibration monitoring sensor 11 and the lifting and transportation of the entire cutter shaft 1, and ensuring the safety of the vibration monitoring sensor 11 during transportation and installation.

[0077] To facilitate the routing of the signal line from the vibration monitoring sensor 11, a threaded plug 14 is provided along its axial direction. The external wireless module is connected to the internal circuitry of the blade via an isolation circuit to prevent high-frequency signal crosstalk. The communication unit is located outside the blade body to communicate with a remote host computer, shielding it from the high temperatures and vibrations inside the blade shaft 1.

[0078] Example 2

[0079] The present application also relates to a tool monitoring method for a rock breaking cutter with a built-in flexible element. Based on the rock breaking cutter with a built-in flexible element described above, the specific steps include:

[0080] S1: The flexible element is excited by the vibration of the cutter ring 16 caused by the cutting force and produces periodic deformation;

[0081] Specifically, a permanent magnet is also provided in the stepped hole to form a constant magnetic field. The flexible element is preferably made of a high-elastic alloy material. Since the flexible element is fixedly connected to the stepped hole of the cutter shaft 1, when the cutter starts to work for excavation, the cutting force of the tool causes the cutter ring 16 to vibrate. The excitation effect of the vibration of the cutter ring 16 will affect the flexible element, causing the flexible element to produce periodic deformation.

[0082] S2: The vibration monitoring sensor 11 detects the vibration frequency of the flexible element and removes noise through the microprocessor to extract the vibration frequency signal of the knife ring excitation;

[0083] Specifically, the flexible element generates an alternating induced electromotive force in the pickup coil in the vibration monitoring sensor 11 by cutting the magnetic lines of force. The frequency of the induced electromotive force is consistent with the vibration frequency of the flexible element. Since the vibration monitoring sensor 11 is connected to the outside of the flexible element, the vibration monitoring sensor 11 will detect the vibration frequency of the flexible element, and the amplitude is proportional to the displacement and speed of the flexible element, respectively.

[0084] It should be noted that the vibration monitoring sensor 11's pickup coil is wound with highly sensitive enameled wire, and the coil impedance matches the frequency of the magnetic field variation. The induced signal output by the pickup coil is a weak sinusoidal wave. The frequency of the pickup coil is the vibration frequency of the flexible element. Common-mode interference is then suppressed by a low-noise instrumentation amplifier. Bandpass filtering is required at the input stage to filter out high-frequency switching noise and low-frequency mechanical vibration interference. Phase-locked amplification technology is used to extract the target frequency band signal using a reference signal synchronized with the vibrating wire frequency. The amplified signal is dynamically adjusted in amplitude through a programmable gain amplifier to ensure the optimization of the ADC input range. A Schmitt trigger converts the sine wave into a square wave, facilitating the microprocessor's accurate frequency capture. A 16-bit or higher resolution ADC is used, and the sampling rate is at least 10 times the highest signal frequency to meet the Nyquist theorem. The microprocessor further eliminates noise through an FIR bandpass filter or FFT spectrum analysis to extract the pure vibration frequency.

[0085] Furthermore, the magnetic field strength of a permanent magnet varies with temperature; rising temperature causes a decrease in magnetic flux. A platinum resistance temperature sensor can be integrated near the magnet to monitor the magnet's temperature in real time. By experimentally measuring the magnet's magnetic induction intensity-temperature curve, a compensation formula can be fitted. A microprocessor reads the temperature data, calculates the current magnetic field strength, and corrects the voltage output by the pickup coil.

[0086] S3: The vibration frequency signal is uploaded to the host computer through the communication unit;

[0087] The communication unit is arranged outside the tool body to communicate with the remote host computer to avoid the influence of high temperature and vibration inside the tool shaft 1. The vibration monitoring sensor 11 uploads the vibration frequency to the host computer through the communication unit, and the host computer analyzes and judges the status of the tool.

[0088] S4: The host computer inputs the extracted vibration signal and the corresponding cutter working condition classification label into the neural network model to automatically extract features and establish a nonlinear functional relationship between the vibration of the flexible element and the cutter excavation state;

[0089] The classification labels of the hob working conditions include, but are not limited to, integer numbers corresponding to normal wear, abnormal wear, breakage, chipping, eccentric wear, loosening of the cutter ring 16, and bearing wear failure of the cutter ring 16.

[0090] Specifically, the sensor system first collects various working condition data of the tool in real time. Each working condition data corresponds to the time series or frequency domain characteristics of the tool in a specific working state.

[0091] Traditional machine learning cannot process large amounts of feature data, requiring complex feature engineering to process the raw data as input variables for the machine learning model. However, for deep learning, manual feature extraction can actually degrade the machine's ability to identify features. Typically, time series or Fourier-transformed frequency domain signals are collected and directly fed into a deep neural network after preprocessing operations such as frequency sampling, cropping, and tensor transformation.

[0092] The network captures the dependencies of time series signals through the LSTM layer, the Conv1d layer quickly extracts the local features of the one-dimensional signal, and the Transformer layer calculates the correlation weights between features and dynamically adjusts the importance of features to achieve weighted fusion of features.

[0093] The network exit is classified by the fully connected layer for working conditions, with a 50% dropout rate set for regularization in the middle. The softmax layer calculates the cross entropy to measure the probability size, and the Top-N prediction results can be obtained.

[0094] Additionally, it's important to note that weights can be initialized using Xavier to ensure that gradients maintain reasonable values. The loss function uses a norm between the predicted value and the true label. Backpropagation is used to continuously optimize the weights and biases of the neural network to ensure that the accuracy of the training and validation sets does not differ significantly, preventing underfitting or overfitting of the model.

[0095] It should be noted that the neural network model can adopt the LSTM-Conv1d-Transformer deep neural network.

[0096] S5: Based on the nonlinear function relationship and the training of the neural network model, the association between variables is automatically learned and extracted to judge and predict the tool status.

[0097] Specifically, the amplitude of the hob cutter shaft 1 is much smaller than that of the cutter ring 16, and it is necessary to amplify it through the flexible part 5. The resulting complex nonlinear functional relationship between the flexible element frequency and the tool working condition under the coupling of multiple influencing factors such as natural frequency, tool body vibration, cutting force, strain, motion state, wear, temperature, etc. can be achieved by constructing a neural network model for large-scale training. Based on high-dimensional input data, it can automatically learn and extract the intrinsic correlation between variables, thereby realizing accurate prediction of tool status and fault diagnosis.

[0098] As a preferred embodiment, based on the nonlinear function relationship and the training of the neural network model, it is possible to automatically learn and extract the association between variables after inputting the corresponding data to predict the tool state, specifically including:

[0099] The sensor component detects the tool's working condition data in real time. Each working condition data corresponds to the time series and frequency domain characteristics of the tool in a specific working state.

[0100] The time series and frequency domain features are preprocessed by the same frequency sampling, clipping and tensor transformation and then input into the neural network model for model training. The neural network model outputs integer numbers, which correspond to various working condition information of the tool to obtain the prediction and fault diagnosis results of the tool.

[0101] Before production begins, a preliminary model pre-training is performed based on historical data from the workshop, and then the bottom weights of the model are fixed. After the tool is put into actual production and used, it will face different working environments. At this time, the neural network model can be fine-tuned based on the data collected during work, and only some weights at the top of the model are updated to improve the accuracy of predictions and the adaptability of the model during actual use. By coupling the vibration frequency of the flexible element with various working condition variables such as cutting force, temperature, and strain, and combining it with a neural network model for modeling, the working state of the tool can be accurately predicted. This method can efficiently handle complex multi-variable relationships and realize real-time monitoring of the tool status.

[0102] Anything not described in this application can be achieved by adopting or drawing on existing technologies.

[0103] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on the differences from other embodiments.

[0104] The foregoing is merely an embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application should all be included within the scope of the claims of the present application.

Claims

1. A rock breaking cutter with a built-in flexible element, characterized in that: Including cutter shaft, cutter ring and sensor assembly; The knife shaft has a stepped hole extending through the axial direction; The cutter ring is rotatably connected to the cutter shaft through a bearing assembly and is used for rock breaking and tunneling; The sensor assembly includes a flexible element and a vibration monitoring sensor; the flexible element is made of a high-elastic alloy material, and the two ends of the flexible element are fixedly connected to the step surface of the stepped hole through a pre-tightening assembly, so that the flexible element is installed in the stepped hole; the vibration monitoring sensor is connected to the outside of the flexible element so that the flexible element can amplify the vibration signal of the tool shaft, thereby realizing real-time monitoring of the working status of the tool by the vibration monitoring sensor; the flexible element includes a flexible part, and the flexible part includes a flexible part body and a flexible connecting part connected to the two ends of the flexible part body; the flexible part body is connected to the packaging shell, the flexible connecting part extends out of the packaging shell and can be partially extended into the connecting groove of the clamping head, and the flexible connecting part is provided with a connecting hole, which is passed through the connecting hole and the connecting groove by a positioning pin to fasten the flexible part to the clamping head.

2. A rock breaking cutter with a built-in flexible element according to claim 1, characterized in that: The flexible element includes a packaging shell, a flexible member and a clamping head; A flexible part is connected inside the packaging shell, and both ends of the flexible part are respectively connected to clamping heads connected to the pre-tightening component; the vibration monitoring sensor is connected to the middle position of the outer side of the packaging shell.

3. A rock breaking roller cutter with a built-in flexible element according to claim 2, characterized in that: The clamping head is of a cone structure, with the small diameter end of the clamping head facing the flexible member and the large diameter end of the clamping head facing the preload assembly; The outer periphery of the small diameter end of the clamping head is provided with an external thread, and the interior of the small diameter end of the clamping head is provided with a connecting groove; the interior of the large diameter end of the clamping head is provided with a positioning hole, and the positioning hole has an internal thread for connecting the pre-tightening component.

4. A rock breaking roller cutter with a built-in flexible element according to claim 3, characterized in that: The flexible element further comprises a clamping nut which is threadedly connected to the outer side of the small diameter end of the clamping head and is fitted into the stepped hole through the clamping nut so that the clamping head is positioned in the stepped hole.

5. The rock breaking roller cutter with a built-in flexible element according to claim 3, characterized in that: The pre-tightening assembly includes a fixing bolt, a pre-tightening nut and a fastening nut; One end of the fixing bolt extends into the positioning hole and is threadedly connected to the clamping head, and the other end of the fixing bolt extends toward the outside of the stepped hole and is connected to the pre-tightening nut. The fastening nut is arranged outside the pre-tightening nut and is fastened to the fixing bolt.

6. The rock breaking roller cutter with a built-in flexible element according to claim 5, characterized in that: The end of the fixing bolt extending toward the outside of the stepped hole is provided with a slot; when the pre-tightening nut is screwed onto the fixing bolt, the slot is pressed against the flexible member abutted by the fixing bolt to prevent twisting.

7. The rock breaking roller cutter with a built-in flexible element according to claim 1, characterized in that: The inner wall of the stepped hole of the knife shaft is provided with an anodized insulating layer; A threaded plug is connected to one end of the stepped hole of the cutter shaft, and an O-ring is connected between the threaded plug and the inner wall of the stepped hole; the threaded plug is also provided with a wiring hole that is connected to the stepped hole, so that a cable can be connected to the vibration monitoring sensor in the stepped hole through the wiring hole; The other end of the stepped hole of the cutter shaft is connected to a bolt ear, and the stepped hole is sealed by a threaded plug and the bolt ear. The gap between the sensor assembly and the inner wall of the stepped hole is filled with silicone damping material, so that the sensor assembly is encapsulated in the stepped hole.

8. A tool monitoring method for a rock breaking cutter with a built-in flexible element, based on the rock breaking cutter with a built-in flexible element according to any one of claims 1 to 7, characterized in that: The specific steps include: The flexible element is excited by the vibration of the cutter ring caused by the cutting force and produces periodic deformation; The vibration monitoring sensor detects the vibration frequency of the flexible element and removes the noise through the microprocessor to extract the vibration frequency signal of the knife ring excitation; The vibration frequency signal is uploaded to the host computer through the communication unit; The host computer inputs the extracted vibration signals and the corresponding cutter working condition classification labels into the neural network model, automatically extracts features, and establishes a nonlinear functional relationship between the vibration of the flexible element and the cutter's tunneling state. Based on the nonlinear function relationship and the training of the neural network model, the association between variables is automatically learned and extracted to judge and predict the tool status.

9. A tool monitoring method for a rock breaking roller cutter with a built-in flexible element according to claim 8, characterized in that: The training of the nonlinear function relationship and the neural network model is used to automatically learn and extract the relationship between variables after inputting the corresponding data to predict the tool state, specifically including: The sensor component detects the tool's working condition data in real time. Each working condition data corresponds to the time series and frequency domain characteristics of the tool in a specific working state. The time series and frequency domain features are preprocessed by the same frequency sampling, clipping and tensor transformation and then input into the neural network model for model training. The neural network model outputs integer numbers, which correspond to various working condition information of the tool to obtain the prediction and fault diagnosis results of the tool.

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